A regio- and stereoselective approach to quaternary centers from chiral trisubstituted aziridines.

J Am Chem Soc

Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, USA.

Published: November 2007

A thorough investigation of a regio- and stereospecific aziridine ring opening reaction presents new synthetic technology for the construction of a variety of quaternary beta-substituted-alpha-amino functional groups. Mild, metal-free reaction conditions allow for application in highly functionalized systems. This reaction has been applied to the challenging stereoselective formation of tertiary alkyl-aryl ethers. The strategy for the formation of these hindered ethers has been investigated using a variety of functionalized aziridines and phenols to determine the scope of the reaction. Other nucleophiles, such as thiolate, azide, and chloride, have also been examined to encompass the synthesis of a broader range of functionalities. This aziridine ring opening reaction manifold has demonstrated utility in assembling: beta-substituted-alpha-amino carboxamides, beta-substituted-alpha-amino esters, beta-substituted-alpha-amino silyl ethers, beta-thio-alpha-amino carboxamides, beta-azido-alpha-amino carboxamides, and beta-halo-alpha-amino carboxamides. Studies to probe the effect of the aziridine substitution patterns show that alkyl aziridines display similar reactivity to alkynyl aziridines, giving insight into mechanistic possibilities.

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http://dx.doi.org/10.1021/ja0758077DOI Listing

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